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Gear Box

Gear box in mechanical systems




The Gear Box block represents an ideal, nonplanetary, fixed gear ratio gear box. The gear ratio is determined as the ratio of the input shaft angular velocity to that of the output shaft.

The gear box is described with the following equations:






ω1Input shaft angular velocity
ω2Output shaft angular velocity
NGear ratio
T1Torque on the input shaft
T2Torque on the output shaft
P1Power on the input shaft
P2Power on the output shaft. Notice the minus sign in computing P2. One of the network rules is that the power flowing through a conserving port is positive if it is removed (dissipated) from the circuit, and is negative if the component generates power into the system.

Connections S and O are mechanical rotational conserving ports associated with the box input and output shaft, respectively. The block positive directions are from S to the reference point and from the reference point to O.


Use the Variables tab in the block dialog box (or the Variables section in the block Property Inspector) to set the priority and initial target values for the block variables prior to simulation. For more information, see Set Priority and Initial Target for Block Variables.


Gear ratio

The ratio of the input shaft angular velocity to that of the output shaft. You can specify both positive and negative values. The default value is 5.


The block has the following ports:


Mechanical rotational conserving port associated with input shaft.


Mechanical rotational conserving port associated with the output shaft.

Introduced in R2007a

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